Timing is everything when you’re planning those Big Lines
Editor’s note: Matt Krane is a ski patroller at Breckenridge Ski Area
By Matt Krane
More than a dozen years ago, a party of four skilled backcountry skiers — one of them, a paramedic with a cell phone —set out to ski the popular north couloir on Buffalo Mountain, just west of Silverthorne.
It was early to mid April if I remember correctly. Six to eight inches of snow overnight turned the upper snowfield glistening white. However, springtime on the calendar does not always correspond to ‘springtime’ in the snowpack. After the upper snowfield broke loose, shallow as the slab was, the avalanche ‘freight-trained’ through the steep narrow couloir (well over 1,000 vertical), killing one person and partially burying and critically injuring a second. The paramedic survived and was able to call the Flight for Life helicopter to the base of the mountain.
Earlier this week, The Breckenridge Ski Patrol hosted its second open house, drawing a crowd of close to 100 at The Maggie, focusing on the transition of snow from the winter snowpack to spring, as well as safe travel in the backcountry. Veteran Himalayan guide and Breckenridge avalanche technician Andy Lapkass gave a captivating presentation about the warming snowpack and the snow metamorphosis that can lead to fantastic steep lines in corn snow, but also to deadly avalanche conditions ‘if you happen to be the impatient type’.
In a nutshell, as the sun gets higher and air temperatures warm, more energy-solar radiation-moves through the snowpack. This reduces the temperature gradient in the pack, leading toward isothermal conditions, more stable ’round’ grains, and an overall increase in stability. This process, however, does not take place overnight, Lapkass explained. It can take several days to several weeks. Throw in the variables of slope elevation, aspect, angle — not to mention ‘creep’, where upper layers in the snowpack can begin the process of slow degradation when free water descends through them to persistent weak layers — and you have many things to consider before heading to steeper terrain in spring and summer riding.
Melt-freeze metamorphism is the main dynamic of a spring/summer snowpack. Free water runs through the entire snowpack, freezing at night (this must happen), rewarming during the day. Lapkass warns that there are daily — if not hourly — fluctuations in the snowpack. Percolation channels through the pack become more unstable during rapid warming and more stable during refreezing. True corn snow results when there is a uniform snowpack which possesses enough stability to stay in place and hold up under the weight of the rider.
There are many things you can do to begin to assess spring/summer snowpack stability. Look around. Is there any evidence of pinwheels (rolling snowballs), wet, loose surface sluffs or even dry/wet slab activity? Was it cloudy the night before? Clouds can act like a blanket, keeping the snowpack from freezing overnight. Was it windy overnight? Wind keeps the snowpack colder. Can you make a snowball, and if so, can you squeeze water out of it? If you can, Lapkass warned, the snowpack has exceeded the dangerous threshold of 7 percent water content, which is very unstable.
A word about wet slides and wet slab avalanches. You do not want to involved in one. The snow, may not move as fast as a dry snow avalanche, but contains astounding amounts of water, weight and debris as it lumbers downslope. If there’s even a question like: Is it too warm, is the sun too high, am I sinking into the snow — back off.
Four years ago at A-Basin, a wet-slab avalanche broke loose on the upper mountain and took the life of a skiing guest. Percolation and very wet snow were key ingredients of a tragedy that affected many, and put wet snow/wet slab formation back into the forefront for some avalanche researchers. Since A-Basin stays open a good deal longer, the concern is greater.
Streamflows can also offer valuable clues. If the water running higher and faster than the last time you saw it, there’s definitely water escaping from the pack.
If you get out of your skis or board, how deep does your boot penetrate? If you go up to your knees, find another aspect — higher and shadier, or have the sense to say no. You’re too late. Or, as Brad Sawtell from the CAIC suggests, if you’re an impatient person and just can’t wait for the sometimes lengthy transition to a uniform snowpack, go to Moab for a week.
When conditions are setting up right, get out early. Like Groucho Marx once said, “You gotta get up early if you wanna get outta bed!” No amount of emphasis can be put on timing things right in the spring/summer backcountry ski season. The steep, the supersteep and narrow can be skied safely. Climbing straight up the couloirs you plan to ride is not out of the question (crampons might be in order). Know your terrain in the summertime. Know your safest routes in and out of the peaks and passes you’ll be traveling in.
After Lapkass’ talk, Breckenridge snow safety director Will Barrett showed some great images which whet the collective appetite of the audience for steep spring skiing.
According to Barrett, “All of May through mid-June is one of the coolest times to be in Colorado.” Barrett and his backcountry buddy, the ever-esoteric yet accessible Mark Beardsley (also an avy tech at Breck), have hit fantastic lines on the north side of Mt. Democrat, the popular ‘south’ or Monte Cristo couloir on Quandary Peak, the countless lines off upper Monte Cristo Gulch, Pacific Peak, the Mosquito Range, Weston Pass (Ptarmigan Peak), and even Mt. Evans.
One of my personal favorites is a snowfield on the west side of Mt. Baldy, approachable by vehicle once Boreas road opens up (okay, so I’m getting older). I peg it at around 1,400 vertical, more when you can ski from the top. It doesn’t get direct sun until mid-late morning. I find it easier to hike in tele or AT boots because there’s plenty of toe-pointing and scree-hopping. The higher you get, the bigger the Ten Mile and Mosquito Ranges grow across the valley. Throw a little Count Basie on the I-pod or maybe a live bluegrass show from Telluride. You can dance your way up to a fantastic view of South Park when you summit. As has been the case a few time when we’ve topped out early, you want to wait for a little sun on the snow,warming temps to assure you that shaving cream hiss of Rocky Mountain Corn.
Filed under: avalanches, climate and weather, Snow and weather, Summit County Colorado, Summit County snow and weather Tagged: | avalanche danger, Colorado backcountry skiing, spring wet snow avalanches, Summit County